Allow for RestTemplate customization

This commit reuses the `RestTemplateBuilder` infrastructure wherever
a `RestTemplate` is required. This allows to customize the rest template
if necessary.

Closes gh-481

initializr-actuator/src/main/java/io/spring/initializr/actuate/autoconfigure/InitializrStatsAutoConfiguration.java

@@ -23,9 +23,13 @@ import io.spring.initializr.actuate.stat.ProjectRequestDocumentFactory;
 import io.spring.initializr.actuate.stat.StatsProperties;
 import io.spring.initializr.metadata.InitializrMetadataProvider;
 
+import org.springframework.boot.autoconfigure.AutoConfigureAfter;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnBean;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
+import org.springframework.boot.autoconfigure.web.WebClientAutoConfiguration;
 import org.springframework.boot.context.properties.EnableConfigurationProperties;
+import org.springframework.boot.web.client.RestTemplateBuilder;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.retry.backoff.ExponentialBackOffPolicy;
@@ -41,6 +45,7 @@ import org.springframework.retry.support.RetryTemplate;
 @Configuration
 @EnableConfigurationProperties(StatsProperties.class)
 @ConditionalOnProperty("initializr.stats.elastic.uri")
+@AutoConfigureAfter(WebClientAutoConfiguration.class)
 class InitializrStatsAutoConfiguration {
 
 	private final StatsProperties statsProperties;
@@ -50,11 +55,13 @@ class InitializrStatsAutoConfiguration {
 	}
 
 	@Bean
+	@ConditionalOnBean(InitializrMetadataProvider.class)
 	public ProjectGenerationStatPublisher projectRequestStatHandler(
-			InitializrMetadataProvider provider) {
+			InitializrMetadataProvider provider,
+			RestTemplateBuilder restTemplateBuilder) {
 		return new ProjectGenerationStatPublisher(
 				new ProjectRequestDocumentFactory(provider), statsProperties,
-				statsRetryTemplate());
+				restTemplateBuilder, statsRetryTemplate());
 	}
 
 	@Bean

initializr-actuator/src/main/java/io/spring/initializr/actuate/stat/ProjectGenerationStatPublisher.java

@@ -30,6 +30,7 @@ import org.springframework.http.RequestEntity;
 import org.springframework.retry.RetryCallback;
 import org.springframework.retry.support.RetryTemplate;
 import org.springframework.scheduling.annotation.Async;
+import org.springframework.util.StringUtils;
 import org.springframework.web.client.RestTemplate;
 
 /**
@@ -49,14 +50,20 @@ public class ProjectGenerationStatPublisher {
 	private final RetryTemplate retryTemplate;
 
 	public ProjectGenerationStatPublisher(ProjectRequestDocumentFactory documentFactory,
-			StatsProperties statsProperties, RetryTemplate retryTemplate) {
+			StatsProperties statsProperties, RestTemplateBuilder restTemplateBuilder,
+			RetryTemplate retryTemplate) {
 		this.documentFactory = documentFactory;
 		this.statsProperties = statsProperties;
 		this.objectMapper = createObjectMapper();
-		this.restTemplate = new RestTemplateBuilder()
-				.basicAuthorization(statsProperties.getElastic().getUsername(),
-						statsProperties.getElastic().getPassword())
-				.build();
+		StatsProperties.Elastic elastic = statsProperties.getElastic();
+		if (StringUtils.hasText(elastic.getUsername())) {
+			this.restTemplate = restTemplateBuilder
+					.basicAuthorization(elastic.getUsername(),
+							elastic.getPassword())
+					.build();
+		} else {
+			this.restTemplate = restTemplateBuilder.build();
+		}
 		this.retryTemplate = retryTemplate;
 	}
 

initializr-actuator/src/test/java/io/spring/initializr/actuate/autoconfigure/InitializrStatsAutoConfigurationTests.java

@@ -0,0 +1,103 @@
+/*
+ * Copyright 2012-2017 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.spring.initializr.actuate.autoconfigure;
+
+import io.spring.initializr.actuate.stat.ProjectGenerationStatPublisher;
+import io.spring.initializr.metadata.InitializrMetadataProvider;
+import io.spring.initializr.web.autoconfigure.InitializrAutoConfiguration;
+import io.spring.initializr.web.autoconfigure.InitializrAutoConfigurationTests;
+import org.junit.After;
+import org.junit.Test;
+
+import org.springframework.beans.DirectFieldAccessor;
+import org.springframework.boot.autoconfigure.web.WebClientAutoConfiguration;
+import org.springframework.boot.test.util.EnvironmentTestUtils;
+import org.springframework.boot.web.client.RestTemplateCustomizer;
+import org.springframework.context.ConfigurableApplicationContext;
+import org.springframework.context.annotation.AnnotationConfigApplicationContext;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.Import;
+import org.springframework.web.client.ResponseErrorHandler;
+import org.springframework.web.client.RestTemplate;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.mockito.Mockito.mock;
+
+/**
+ * Tests for {@link InitializrStatsAutoConfiguration}.
+ *
+ * @author Stephane Nicoll
+ */
+public class InitializrStatsAutoConfigurationTests {
+
+	private ConfigurableApplicationContext context;
+
+	@After
+	public void close() {
+		if (this.context != null) {
+			this.context.close();
+		}
+	}
+
+	@Test
+	public void customRestTemplateBuilderIsUsed() {
+		load(CustomRestTemplateConfiguration.class,
+				"initializr.stats.elastic.uri=http://localhost:9200");
+		assertThat(this.context.getBeansOfType(ProjectGenerationStatPublisher.class))
+				.hasSize(1);
+		RestTemplate restTemplate = (RestTemplate) new DirectFieldAccessor(
+				this.context.getBean(ProjectGenerationStatPublisher.class))
+				.getPropertyValue("restTemplate");
+		assertThat(restTemplate.getErrorHandler()).isSameAs(
+				CustomRestTemplateConfiguration.errorHandler);
+	}
+
+	private void load(Class<?> config, String... environment) {
+		AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext();
+		EnvironmentTestUtils.addEnvironment(ctx, environment);
+		if (config != null) {
+			ctx.register(config);
+		}
+		ctx.register(WebClientAutoConfiguration.class,
+				InitializrStatsAutoConfiguration.class);
+		ctx.refresh();
+		this.context = ctx;
+	}
+
+	@Configuration
+	static class InfrastructureConfiguration {
+
+		@Bean
+		public InitializrMetadataProvider initializrMetadataProvider() {
+			return mock(InitializrMetadataProvider.class);
+		}
+	}
+
+	@Configuration
+	@Import(InfrastructureConfiguration.class)
+	static class CustomRestTemplateConfiguration {
+
+		private static final ResponseErrorHandler errorHandler = mock(ResponseErrorHandler.class);
+
+		@Bean
+		public RestTemplateCustomizer testRestTemplateCustomizer() {
+			return b -> b.setErrorHandler(errorHandler);
+		}
+	}
+
+}

initializr-actuator/src/test/java/io/spring/initializr/actuate/stat/ProjectGenerationStatPublisherTests.java

@@ -25,6 +25,7 @@ import io.spring.initializr.generator.ProjectRequest;
 import org.junit.Before;
 import org.junit.Test;
 
+import org.springframework.boot.web.client.RestTemplateBuilder;
 import org.springframework.http.HttpMethod;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.MediaType;
@@ -54,7 +55,7 @@ public class ProjectGenerationStatPublisherTests extends AbstractInitializrStatT
 				new ProjectRequestDocumentFactory(createProvider(getMetadata()));
 		this.retryTemplate = new RetryTemplate();
 		this.statPublisher = new ProjectGenerationStatPublisher(documentFactory,
-				properties, retryTemplate);
+				properties, new RestTemplateBuilder(), retryTemplate);
 		mockServer = MockRestServiceServer.createServer(
 				this.statPublisher.getRestTemplate());
 	}